GB1590932A

GB1590932A - Fungicidal agents

Info

Publication number: GB1590932A
Application number: GB4882/78A
Authority: GB
Original assignee: Bayer AG
Current assignee: Bayer AG
Priority date: 1977-02-11
Filing date: 1978-02-07
Publication date: 1981-06-10
Also published as: DE2705676A1; JPS53101532A; ZA78822B; DK61478A; CA1106757A; CS194197B2; BR7800791A; TR19543A; SE7801525L; PL109892B1; IL54003A0; AU3324278A; FR2379983A1; NL7801578A; GB1590933A; PL204556A1; DD134719A5; BE863850A; PT67627B; ATA94278A

Description

(54) FUNGICIDAL AGENTS (71) We, BAYER AKTIENGESELLSCHAFT, a body corporate, organised under the laws of Germany, of Leverkusen, Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to the use as fungicides of certain 2,4 dichlorophenyl - imidazolyl - ethan - ones.

It has already been disclosed that 3,3 - dimethyl - I - phenoxy - 1 - imidazolyl - butan - 2 - ols possess a fungicidal activity (see British Patent Specification No. 1,421,689). However, their action is not always completely satisfactory, in particular when low application amounts and concentrations are used.

In British Patent Specification No. 1,419,734, it is disclosed that l-(optionally substituted aryloxy) - 1 - imidazolyl - 2- (optionally substituted aryl)-ethan - 2 zones have fungicidal activity. However, there is no disclosure of the 2,4dichlorophenyl compounds to which this invention relates or their superior fungicidal activity.

It has now been found that the 2,4 - dichlorophenyl - imidazolyl - ethan ones of the general formula

in which A represents a keto group, X represents halogen, alkyl or optionally substituted phenyl and n represents 0, 1, 2 or 3, the X's being selected independently of one another when n is 2 or 3, and their salts have powerful fungicidal properties.

The present invention therefore provides a fungicidal composition containing as active ingredient a compound of the formula (I), or a salt thereof, in admixture with a solid or liquefied gaseous diluent or carrier or in admixture with a liquid diluent or carrier containing a surface-active agent.

The present invention also provides a method of combating fungi which comprises applying to the fungi, or to a habitat thereof, a compound of the formula (I), or a salt thereof, alone or in admixture with a diluent or carrier.

Preferably, in formula (I), X represents fluorine, chlorine, bromine, iodine, stRaight-chain or branched alkyl with 1 to 4 carbon atoms, or phenyl which is optionally substituted by halogen (especially chlorine) and n represents 0, 1 or 2.

Examples which may be mentioned of particularly active compounds to be used according to the invention are: I - (2 - chlorophenoxy) - 2 - (2,4 dichlorophenyl) - 1 - imidazol - I yl - ethan - 2 - one, I - (2 isopropylphenoxy) - 2 -(2,4 - dichlorophenyl) - I - imidazol - 1 - yl - ethan - 2 one, I - (2 - methylphenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - I - yl ethan - 2 - one, 1 - (2 - chloro -- 4 - methylphenoxy) - 2 - (2,4 dichlorophenyl) - 1 - imidazol - 1 yl - ethan - 2 - one, I - (4 bromophenoxy) - 2 - (2,4 - dichlorophenyl) - I - imidazol - 1 - yl - ethan - 2 one, 1 - (4 - iodophenoxy) - 2 - (2,4 - dichlorophenyl) - I - imidazol - 1 - yl - ethan - 2 - one, 1 - (2,6 - dichlorophenoxy) - 2 - (2,4 - dichlorophenyl) - I imidazol - 1 - yl - ethan - 2 - one, 1 - (2,5 - dichlorophenoxy)- 2 - (2,4 dichlorophenyl) - 1 - imidazol - 1 - yl - ethan - 2 - one, 1 - (3 - fluorophenoxy) 2 - (2,4 - dichlorophenyl)- 1 - imidazol - 1 - yl - ethan - 2 - one, 1 - (3 - bromophenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - 1 - yl - ethan - 2 one, 1 - (4 - methylphenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - 1 - yl ethan - 2 - one, 1 - (4 - ethylphenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - 1 - yl - ethan - 2 - one, 1 - (3 - methylphenoxy) - 2 - (2,4 dichlorophenyl)- I - imidazol - 1 - yl - ethan - 2 - one, I - (2 methylphenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - 1 - yl - ethan - 2 - one, 1 - (4 - chloro - 2 - methylphenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - I - yl - ethan - 2 - one, 1 - (4 - bromo - 2 - methylphenoxy) - 2 (2,4 - dichlorophenyl) - I - imidazol - I - yl - ethan - 2 - one, 1 - (4 - fluoro 2 - methylphenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - 1 - yl - ethan 2 - one, 1 - (4 - iodo - 2 - methylphenoxy) - 2 - (2,4 - dichlorophenyl) - I imidazol- 1 - yl - ethan - 2 - one, 1 - (2,3 - dimethylphenoxy) - 2 - (2,4 dichlorophenyl) - 1 - imidazol - 1 - yl - ethan - 2 - one, 1 - (4,2',4' dichlorobiphenylyloxy) - 2 - (2,4 - dichlorophenyl) - I - imidazol - 1 - yl - ethan - 2 - one, 1 - (4 - 2,4' - dichlorobiphenylyloxy) - 2 - (2,4 dichlorophenyl)- 1 - imidazol - 1 - yl - ethan - 2 - one), I - (4 - 4' bromobiphenylyloxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - 1 - yl - ethan 2 - one, and 1 - (4 - 2 - chlorobiphenylyloxy) - 2 - (2,4 - dichlorophenyl) - I imidazol- 1 - yl- ethan - 2 - one. Further compounds are given in the preparative Examples to be found later in this text.

The active compounds to be used according to the invention, and their salts, have not yet been described in the literature. However, they can be prepared by reacting 1 - bromo - 2 -(2,4 - dichlorophenyl) - 1 - phenoxy - ethan - 2 - ones of the formula

in which X and n have the meanings stated above, with imidazole in the presence of an inert organic solvent, for example acetonitrile, and in the presence of an acidbinding agent, for example potassium carbonate or an excess of imidazole, at temperatures between 0 and 1500C, preferably at 60 to 1200C. The compounds of the formula (I) are isolated in a manner which is generally customary.

The 1 - bromo - 2 - (2,4 - dichlorophenyl) - 1 - phenoxy - ethan - 2 - ones of the formula (II) to be used as starting materials have not yet been described in the literature. However, they can be prepared by known processes by reacting corresponding phenols with w - bromo - 2,4 - dichloroacetophenone and subsequently replacing the active hydrogen atom which still remains, by bromine in the customary manner.

Preferred salts of the compounds of the formula (I) are from the standpoint of phytotoxicity, physiologically acceptable salts, these being generally salts with physiologically acceptable acids. The preferred acids include hydrogen halide acids (for example hydrobromic acid and, in particular, hydrochloric acid), phosphoric acid, nitric acid, monofunctional and bifunctional carboxylic acids and hydroxycarboxylic acids (for example acetic-acid, citric acid, sorbic acid and lactic acid), and l,5-naphthalene-disulphonic acid.

The active compounds according to the invention exhibit a powerful fungitoxic action. They do not damage crop plants in the concentrations required for combating fungi. For these reasons, they are suitable for use as plant protection agents for combating fungi. Fungitoxic agents are employed in plant protection for combating Plasmodiophoromycetes, Oomycetes, Chytridiomycetes, Zygomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes.

The active compounds according to the invention have a broad spectrum of action and can be used against parasitic fungi which attack above-ground parts of plants or which attack the plants through the soil, as well as against seed-borne pathogens.

They display a particularly good activity against parasitic fungi on aboveground parts of plants.

As plant protection agents, the active compounds according to the invention can be used with particularly good success for combating powdery mildew fungi, for example for combating powdery mildew of cucumbers (Erysiphe cichoriacearum), as well as against cereal diseases, for example cereal rust.

As plant protection agents, the compounds according to the invention can be used for the treatment of soil, for the treatment of seed and for the treatment of above-ground parts of plants.

The active compounds can be converted into the customary formulations, such as solutions, emulsions, wettable powders, suspensions, powders, dusting agents, foams, pastes, soluble powders, granules, aerosols, suspension-emulsion concentrates, seed-treatment powders, natural and synthetic materials impregnated with active compound, very fine capsules in polymeric substances, coating compositions for use on seed, and formulations used with burning equipment, such as fumigating cartridges, fumigating cans and fumigating coils, as well as ULV (ultra-leuco-volume) cold mist and warm mist formulations.

These formulations may be produced in known manner, for example by mixing the active compounds with extenders, that is to say liquid or liquefied gaseous or solid diluents or carriers, optionally with the use of surface-active agents, that is to say emulsifying agents and/or dispersing agents and/or foam-forming agents. In the case of the use of water as an extender, organic solvents can, for example, also be used as auxiliary solvents.

As liquid solvents diluents or carriers, especially solvents, there are suitable in the main, aromatic hydrocarbons, such as xylene, toluene or alkyl naphthalenes, chlorinated aromatic or chlorinated aliphatic hydrocarbons, such as chlorobenzenes, chloroethylenes or methylene chloride, aliphatic or alicyclic hydrocarbons, such as cyclohexane or paraffins, for example mineral oil fractions, alcohols, such as butanol or glycol as well as their ethers and esters, ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, or strongly polar solvents, such as dimethylformamide and dimethylsulphoxide, as well as water.

By liquefied gaseous diluents or carriers are meant liquids which would be gaseous at normal temperature and under normal pressure, for example aerosol propellants, such as halogenated hydrocarbons as well as butane, propane, nitrogen and carbon dioxide.

As solid carriers there may be used ground natural minerals, such as kaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth, and ground synthetic minerals, such as highly-dispersed silicic acid, alumina and silicates. As solid carriers for granules there may be used crushed and fractionated natural rocks such as calcite, marble, pumice, sepiolite and dolomite, as well as synthetic granules of inorganic and organic meals, and granules of organic material such as sawdust, coconut shells, maize cobs and tobacco stalks.

As emulsifying and/or foam-forming agents there may be used non-ionic and anionic emulsifiers, such as polyoxyethylene-fatty acid esters, polyoxyethylenefatty alcohol ethers, for example, alkylaryl polyglycol ethers, alkyl sulphonates, alkyl sulphates, aryl sulphonates as well as albumin hydrolysis products. Dispersing agents include, for example, lignin sulphite waste liquors and methylcellulose.

The active compounds according to the invention can be present in the formulations as a mixture with other active compounds, such as fungicides, insecticides, acaricides, nematicides, herbicides, bird repellants, growth factors, plant nutrients and agents for improving soil structure.

The formulations in general contain from 0.1 to 95 per cent by weight of active compound, preferably from 0.5 to 90 per cent.

The active compounds can be used as such, as their formulations or as the use forms prepared therefrom by further dilution, such as ready-to-use solutions, emulsions, suspensions, powders, pastes and granules. They may be used in the customary manner, for example by watering, spraying, atomising, dusting, scattering, dry dressing, moist dressing, wet dressing, slurry dressing or encrusting.

Especially when used as leaf fungicides, the active compound concentrations in the use forms can be varied within a fairly wide range. They are, in general, from 0.00001 to 0.1 per cent by weight, preferably from 0.0001 to 0.05 per cent.

For treatment of seed, amounts of active compound of from 0.001 to 50 g per kilogram of seed, preferably from 0.01 to 10 g, are generally employed.

The present invention further provides crops protected from damage by fungi by being grown in areas in which immediately prior to and/or during the time of the growing a compound of the formula (I), or a salt thereof, was applied alone or in admixture with a diluent or carrier.

It will be seen that the usual methods of providing a harvested crop may be improved by the present invention.

The fungicidal activity of the compounds of this invention is illustrated by the following biotest Examples.

In these Examples, the compounds according to the present invention are each identified by the number (given in brackets) of the corresponding preparative Example, which will be found later in this specification.

The known comparison compounds are identified as follows:

Example A Shoot treatment test/cereal rust (leaf-destructive mycosisprotective To produce a suitable preparation of active compound was taken up in 25 parts by weight of dimethylformamide and 0.06 part by weight of alkylaryl polyglycol ether and then 975 parts by weight of water were added. The concentrate was diluted with water to the desired final concentration of the spray liquor.

To test the protective activity, one-leaved young wheat plants of the Michigan Amber variety were inoculated with a uredospore suspension of Puccinia recondita in 0.1% strength aqueous agar. After the spore suspensions had dried on, the wheat plants were sprayed with the preparation of active compound until dew-moist and were placed, for incubation, in a greenhouse for 24 hours at about 20 deg. C and 100% relative atmospheric humidity.

After 10 days' dwell time of the plants at a temperature of 20 deg. C and 80- 90% atmospSheric humidity, the occurrence of rust pustules on the plant was evaluated. The degree of infection was expressed as a percentage of the infection of the untreated control plants. 0% denoted no infection and 100% denoted the same degree of infection as in the case of the untreated control. The active compound was the more active, the lower was the degree of rust infection.

The active compounds, active compound concentrations in the spray liquor and degrees of infection can be seen from the table which follows: TABLE B Shoot treatment test/cereal rust/protective Active compound concentration in the.

spray liquor in % by Infection in /n of the Active compounds weight untreated control untreated 100 (B) 0.025 50.0 (A) 0.025 58.8 (3) 0.025 23.8 (4) 0.025 23.8 Preparative Examples Example 1

103 g (0.26 mol) of 1 - bromo - 1 - (4 - chlorophenoxy)- 2 - (2,4 dichlorophenyl) - ethan - 2 - one were added dropwise at the boil to 65 g (1 mol) of imidazole in 650 ml of acetonitrile. The mixture was heated under reflux for 40 hours. Thereafter, the solvent was distilled off in vacuo, the residue was taken up in 500 ml of methylene chloride and the methylene chloride solution was extracted by shaking four times with 250 ml of water each time. The organic phase was dried over sodium sulphate and concentrated by distilling off the solvent in vacuo. The residue was taken up in 1,000 ml of acetone and 47 g (0.26 mol) of 1,5-naphthalenedisulphonic acid in 100 ml of acetone were added. The precipitate which formed was filtered off and boiled up with 100 ml of acetone. 200 ml of sodium bicarbonate solution and 500 ml of methylene chloride were added to the residue. The organic phase was separated off, washed with 200 ml of water and concentrated by distilling off the solvent in vacuo. The residue was taken up in 200 ml of ether and dry hydrogen chloride was added in excess. After distilling off the ether in vacuo, the oily residue was recrystallized from acetone. 31.6 g (29 /n of theory) of 1 - (4 chlorophenoxy) - 2 - (2,4 - dichlorophenyl) - 1 - imidazol - 1 - yl - ethan - 2 one hydrochloride of melting point 146-1480C. were obtained.

The compounds which follow in Table 1 were obtained analogously to the Examples given above.

TABLE 1

Example No. Xn A Melting point ("C) 2 2,4-Cl2 CO 205-215(.HCl) 3 4 < Cl 145-148 (.HCl) 4 4 < CO 160 -162(.H Cl) 5 4-F CO 160(.HCl) 6 - CO 162-168 (.HCl) 7 2,6-Cl2 CO 180(.HCl) 8 3-C1 CO 168-171 (.HCl) 9 4-CH3 CO IIO(.H Cl) 10 4-Cl, 2-CH2 CO 177-178 (.HCl)

Claims

WHAT WE CLAIM IS:

1. A fungicidal composition containing as active ingredient a 2,4dichlorophenyl-imidazolyl-ethan-one of the general formula

in which A represents a keto group, X represents halogen, alkyl or optionally substituted phenyl and n represents 0, 1, 2 or 3, the X's being selected independently of one another when n is 2 or 3, or a salt thereof, in admixture with a solid or liquefied gaseous diluent or carrier or in admixture with a liquid diluent or carrier containing a surface-active agent.

2. A composition according to claim 1, which contains a compound of the formula (I), or a salt thereof, in which X represents fluorine, chlorine, bromine, iodine, straight-chain or branched alkyl with 1 to 4 carbon atoms, or phenyl which is optionally substituted by halogen and n represents 0, 1 or 2.

3. A composition according to claim 1, which contains a compound of the formula (I), or a salt thereof, that is disclosed in any one of Examples 1 to 10.

4. A composition according to claim 1 or 2, which contains a compound of the formula (I) or a salt thereof with a phytophysiologically tolerated acid.

5. A composition according to any of claims 1 to 4 containing from 0.1 to 95 /n of the active compound, by weight.

6. A method of combating fungi which comprises applying to the fungi, or to a habitat thereof, a compound of the formula (I), or a salt thereof, as specified in any of claims 1 to 4 alone, or in admixture with a diluent or carrier.

7. A method according to claim 6 in which a composition is used containing from 0.00001 to 0.1% of the active compound, by weight.

8. A method according to claim 7 in which a composition is used containing from 0.0001 to 0.05% of the active compound, by weight.

9. A method accoding to claim 6, in which the active compound is applied to seed in an amount of 0.001 to 50 g per kg of seed.

10. A method according to claim 9, in which the active compound is applied to seed in an amount of 0.01 to 10 g per kg of seed.

11. Crops protected from damage by fungi by being grown in areas in which immediately prior to and/or during the time of the growing a compound of the formula (I), or a salt thereof, as specified in any of claims 1 to 4 was applied alone or in admixture with a diluent or carrier.